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Difference between the U. S. Survey Foot and the International Foot

Conversions:
1 Meter = 3.280833333 US Survey Feet (you can append as many 3's as you like for the desired degree of precision)

1 US Survey Foot = 1 Meter divided by 3.280833333 (you can append as many 3's as you like for the desired degree of precision)
OR
1 US Survey Foot = 0.30480060960 Meters

1 International Foot = 0.3048 meters

1 Meter = 1 International Foot divided by 0.3048
OR
1 Meter = 3.280839895 International Feet

Background:
When the metric system was originally invented in the early 1800's, the meter was defined as 1 ten millionth of the distance from the equator to the North Pole. At that time, the official conversion of English to metric units was exactly 39.370 inches being equal to one meter.

It was discovered, however, that the definition of a meter was not completely accurate since the shape of the earth was not a true ellipsoid. In the 1950's, the definition of the meter was changed to be so many times the wavelength of a certain type of light. The English conversion factor was then set to 2.540 centimeters being equal to one inch. Thus, there are two conversions between metric and English, with the resulting values being very close, but not identical.

A foot based on the older pole defined system is referred to as a U. S. Survey Foot; a foot based on the newer wavelength definition is referred to as an International Foot.